A pruning shear device includes a pair of pruning shears with a lug located at a rear end of a cutter blade thereof, and a switch unit including a position-limiting member movable between a first position where the position-limiting member is abutted against the lug for enabling the pruning shears to perform in a normal operating mode for cutting off small tree branches through a single-stage force-applying operation and a second position where the position-limiting member is kept away from the lug for enabling the pruning shears to perform in an effort-saving operating mode for cutting off large tree branches through a multi-stage force-applying operation.
